#include <iostream>
using namespace std;

//static int number = 500;
int number = 500;

namespace wd
{
extern int number3;
//number3 = 400;
int number = 1;
 
void display(){
    cout << "hello" << endl;
}
}//end of namespace wd

namespace cpp
{
int number = 2;

void display(){
    cout << "world" << endl;
}

}

void test0(){
    cout << wd::number3 <<endl;
}


int main(void){
    cout << number <<endl;
    using cpp::number;
    cout << number <<endl;
    //test0();
    return 0;
}

